Update WetKit Ember for Issue #2303747 by gdaw: Fixed admin theme wetkit_ember causes Problems in Metatag option to 'Browse available tokens'.
Update WetKit Core for Issue #2289085 by lampson: Added Allow user to delete the current non-published revision.
Merge pull request #1509 from sylus/7.x-1.x

Prepare for 1.6 release.